Bob & Carol & Ted & Alice meets a considerably tamed Van Wilder for a mediocre romp in the Hamptons. Booze-fueled antics – and Don Johnson! – ensue. To be fair, A Good Old Fashioned Orgy has no lie in its title. There is an orgy in the third act, but whether or not that's a good thing depends on both your sense of humor and the film's unexciting R rating. But hey, beneath all those bikinis and wealth-infused East Hampton tans is a raunchy comedy that plays suspiciously like The Big Chill, scantily clad.

Labor Day weekend is just around the corner when Eric (Saturday Night Live's Sudeikis) discovers to his dismay that his father (an unbilled Don Johnson) is putting their sprawling summer mansion up for sale. Formerly the site of a series of themed bacchanals that'd give Delta House a run for its togas, Eric and his close-knit circle of friends are understandably forlorn at the prospect of losing their party palace. No more guacamole dip served from a toilet, no more pseudo clever drunken repartee? Heaven forfend! And thus a plan is hatched for one final soiree at which everything – clothes, emotions, petty jealousies, and, yes, bromance – will be shed in spectacular fashion. Or so they hope.

Take away the orgy aspect (not that the producers would allow it) and what you're left with is a mediocre meditation on a sextet of thirtysomethings running head-on into the wall of their own fast-vanishing sexual peaks. As leader of the pack, Eric reminds everyone that his generation came of age in the darkest days of AIDS: "Our parents were freaks, we know the kids today are freaks, but we got screwed because we were so terrified of getting AIDS." Let the revel commence.

A Good Old Fashioned Orgy's comic strength lies in its well-rounded cast, most of them TV or Funny or Die veterans. Among them are Tyler Labine (Tucker & Dale vs. Evil) as the overweight but genuinely funny sidekick, Mike; über-perky Leslie Bibb as the potentially evil real estate agent Eric falls for; and Nick Kroll as Adam, the BlackBerry-addicted Jewish Wall Streeter with an ungodly schvantz. The group may be little more than an assemblage of youthful archetypes, but they play it light and easy, and in the end, A Good Old Fashioned Orgy is an amiably goofy riff on what it means to grow older in an increasingly youth-dominated culture. But wait – isn't 40 the new 30? Whatever. As one character says, "It's supposed to be fun, not The Accused.”